Cheryl Bost - FDA Advisory Hearing

August 5, 2013

My name is Cheryl Bost, I'm 46 and I am currently in stage four renal failure due to autosomal dominant polycystic kidney disease (PKD). I'm here before you today to share my family's story and ask that you approve Otsuka's request to move tolvaptan forward as another avenue for families suffering with PKD.

As a teenager, I had no idea what polycystic kidney disease was and I had no idea it was in my family. My oldest brother Jeff went off to college and joined the lacrosse team. During one game, he was hit in the side with a lacrosse stick and soon after blood was detected in his urine. After a medical review, it was determined that he had indeed inherited PKD from my mom's side of the family. Soon, my other brother Bob and I were tested and all three of us had cysts on our kidneys and were diagnosed with PKD. We learned that my mom had PKD, my mom's cousins, my grandfather, and others on her side of the family had PKD. We were monitored, but not much was discovered at that time so life didn't seem too different until 1995.

In 1995, my mom's kidneys were starting to fail. She was on many medications and often sick or just not feeling well. She was placed on a transplant list and the wait started. Luckily in 1997 a perfect cadaver match was found for my mom 2 weeks before she was scheduled for dialysis. We were blessed and very fortunate. My mom was 59 when she received her transplant and has had it now for 16 years. My brothers and I thought well, if we've been taking care of our kidneys since early diagnosis then we'll be at least in our 60's before we are faced with renal failure. We became very active with the PKD Foundation and donated and raised thousands of dollars for research in hopes of developments just like this new pharmaceutical treatment with tolvaptan.

Our theory didn't come through to fruition. In 2010, my oldest brother Jeff, at age 49, reached stage 4 renal failure and went on a transplant list. Fortunately, his wife Kathy was a match and they had their transplant surgery in August of 2011. Soon after in 2011, at age 48, my bother Bob reached stage 4 renal failure and went on a transplant list. Once again, fortunately for him, his wife Courtney was a match and in June 2012 they successfully had their transplant surgery. And in September 2012, at age 45, I reached stage 4 renal failure and was placed on a transplant list. Now, my mom didn't do her job and pick out a husband for me that matched for a transplant, so I'm still on the transplant list at Johns Hopkins and pray every day to find a donor to match my O negative blood type.

As you can see with my family, stage 4 renal failure is reaching this generation at a much younger age. I work full time, but I am exhausted every day and I take a lot of medications to balance out my lack of kidney function. Each month I get blood work done and medications are adjusted. I have constant back pain, indigestion, and more. My kidneys are the size of Nerf footballs with some cysts as large as 4 centimeters. I'm hoping I can get a transplant before I am forced to go on dialysis.

That's not where our family story ends. I have three nieces and a nephew. Currently all three nieces have PKD and that is why I'm here. They need more options. Transplantation and dialysis are not cures, and we need to look at drugs and other research that will hopefully slow the formation of cysts so they can live longer and pain free lives.

I'm not fooled to think that tolvaptan is a miracle drug, but it's a huge step in the right direction. I'm thankful that a pharmaceutical company is willing to take the time and money to do the trials and work to get this drug on the market. Once on the market and more widespread, then we can hopefully continue the research and more companies will take up this endeavor and we'll find even more ways to stop the progression of this disease.

My family story is not unique. Autosomal dominant polycystic kidney disease is the most common type of inherited kidney disease. Families like mine all over of this country and all over this world are working to raise awareness and raise money in order to increase the amount of research that could lead to cures. We're asking you to move this drug forward so this can be another tool in our toolbelt to help slow this disease and improve the quality of life for those with PKD.